The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
The present invention relates generally to a winch drum and, in particular, to a multi-element drum assembly.
Wireline winch drums are typically used in oilfield operations. In certain applications, a logging tool is attached to a cable and the cable is spooled on a drum. A cable tension applied to the drum is determined by the cable length and type, the tool string weight, the well-bore geometry, and formation characteristics, for example. The cable tension generates two types of load on the drum: a pressure applied on a core of the drum; and a pressure applied on a flange of the drum.
The core of the drum is typically exposed to the resulting tension forces from cable loads applied through the flanges. A large bending moment is typically created at a junction (i.e. core/flange junction) of the core and each of the flanges. The various loads applied to the drum often generate stresses at the core/flange junction. Accordingly, stresses at the core/flange junction pose a risk for crack initiation due to the fatigue condition created during the cyclical loading and unloading during normal loggings.
High stresses in a conventional core-flange junction cannot be resolved using traditional methods, such as reinforcement.
It is always desirable to provide a drum and a method of assembling the drum, wherein the drum and the method minimize a stress and fatigue of the drum at a core/flange junction while maximizing load capacity of the drum.